unwebbed
Unwebbed is a term used to describe a digit, typically a finger or toe, that lacks the connecting membrane found in webbed feet or hands. This lack of webbing is characteristic of most terrestrial vertebrates, including humans. In contrast, webbed digits are an adaptation seen in many aquatic or semi-aquatic animals, such as ducks, frogs, and otters, where the webbing increases the surface area of the foot or hand, providing greater propulsion through water. The absence of webbing in humans and many other land animals reflects their evolutionary divergence from aquatic ancestors and their adaptation to terrestrial locomotion. While some animals may have vestigial webbing, it is generally not functional for swimming. The genetic factors determining the presence or absence of webbing are complex and can be influenced by various developmental genes.